/*
 * Copyright 2016 Code Above Lab LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.codeabovelab.dm.gateway.api;

import com.codeabovelab.dm.common.gateway.ConnectionEvent;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.Assert;

import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * Hub for event from connections
 */
@Component
public class ConnectionEventHub implements ConnectionEventListener {

    private final Set<ConnectionEventListener> listeners = new CopyOnWriteArraySet<>();

    @Autowired
    public ConnectionEventHub() {
    }

    public void addConnectionEventListener(ConnectionEventListener listener) {
        listeners.add(listener);
    }

    @Override
    public void listen(ConnectionEvent event) {
        Assert.notNull(event, "Event is null");
        sendToListeners(event);
    }

    private void sendToListeners(ConnectionEvent event) {
        for(ConnectionEventListener listener: listeners) {
            listener.listen(event);
        }
    }
}
